In a series of tweets, the PM mourned the death of "dear friend" Cho Ramaswamy, called him "a multidimensional personality, towering intellectual, great nationalist and fearless voice who was respected and admired".

Ramaswamy had a personal rapport with many politicians in the country.

Prime Minister Narendra Modi and Late Tamil Nadu chief minister and AIADMK general secretary J Jayalalithaa had called on him when he was seriously ill early this year.

Modi later posted two videos of an event he attended in Chennai.

"The feisty Cho Ramaswamy introduces me as the 'Merchant of Death.' Do watch this memorable interaction," Modi posted on Twitter and in another tweet, he posted his response.

The feisty Cho Ramaswamy introduces me as the 'Merchant of Death.' Do watch this memorable interaction. https://t.co/2FsF64sVvH